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BGP: Extend 'next hop keep' and 'next hop self' options
[thirdparty/bird.git] / proto / bgp / bgp.h
1 /*
2 * BIRD -- The Border Gateway Protocol
3 *
4 * (c) 2000 Martin Mares <mj@ucw.cz>
5 * (c) 2008--2016 Ondrej Zajicek <santiago@crfreenet.org>
6 * (c) 2008--2016 CZ.NIC z.s.p.o.
7 *
8 * Can be freely distributed and used under the terms of the GNU GPL.
9 */
10
11 #ifndef _BIRD_BGP_H_
12 #define _BIRD_BGP_H_
13
14 #include <stdint.h>
15 #include <setjmp.h>
16 #include "nest/bird.h"
17 #include "nest/route.h"
18 #include "nest/bfd.h"
19 //#include "lib/lists.h"
20 #include "lib/hash.h"
21 #include "lib/socket.h"
22
23 struct linpool;
24 struct eattr;
25
26
27 /* Address families */
28
29 #define BGP_AFI_IPV4 1
30 #define BGP_AFI_IPV6 2
31
32 #define BGP_SAFI_UNICAST 1
33 #define BGP_SAFI_MULTICAST 2
34 #define BGP_SAFI_MPLS 4
35 #define BGP_SAFI_MPLS_VPN 128
36 #define BGP_SAFI_VPN_MULTICAST 129
37 #define BGP_SAFI_FLOW 133
38
39 /* Internal AF codes */
40
41 #define BGP_AF(A, B) (((u32)(A) << 16) | (u32)(B))
42 #define BGP_AFI(A) ((u32)(A) >> 16)
43 #define BGP_SAFI(A) ((u32)(A) & 0xFFFF)
44
45 #define BGP_AF_IPV4 BGP_AF( BGP_AFI_IPV4, BGP_SAFI_UNICAST )
46 #define BGP_AF_IPV6 BGP_AF( BGP_AFI_IPV6, BGP_SAFI_UNICAST )
47 #define BGP_AF_IPV4_MC BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MULTICAST )
48 #define BGP_AF_IPV6_MC BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MULTICAST )
49 #define BGP_AF_IPV4_MPLS BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MPLS )
50 #define BGP_AF_IPV6_MPLS BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MPLS )
51 #define BGP_AF_VPN4_MPLS BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MPLS_VPN )
52 #define BGP_AF_VPN6_MPLS BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MPLS_VPN )
53 #define BGP_AF_VPN4_MC BGP_AF( BGP_AFI_IPV4, BGP_SAFI_VPN_MULTICAST )
54 #define BGP_AF_VPN6_MC BGP_AF( BGP_AFI_IPV6, BGP_SAFI_VPN_MULTICAST )
55 #define BGP_AF_FLOW4 BGP_AF( BGP_AFI_IPV4, BGP_SAFI_FLOW )
56 #define BGP_AF_FLOW6 BGP_AF( BGP_AFI_IPV6, BGP_SAFI_FLOW )
57
58
59 struct bgp_write_state;
60 struct bgp_parse_state;
61 struct bgp_export_state;
62 struct bgp_bucket;
63
64 struct bgp_af_desc {
65 u32 afi;
66 u32 net;
67 u8 mpls;
68 u8 no_igp;
69 const char *name;
70 uint (*encode_nlri)(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, uint size);
71 void (*decode_nlri)(struct bgp_parse_state *s, byte *pos, uint len, rta *a);
72 void (*update_next_hop)(struct bgp_export_state *s, eattr *nh, ea_list **to);
73 uint (*encode_next_hop)(struct bgp_write_state *s, eattr *nh, byte *buf, uint size);
74 void (*decode_next_hop)(struct bgp_parse_state *s, byte *pos, uint len, rta *a);
75 };
76
77
78 struct bgp_config {
79 struct proto_config c;
80 u32 local_as, remote_as;
81 ip_addr local_ip; /* Source address to use */
82 ip_addr remote_ip;
83 struct iface *iface; /* Interface for link-local addresses */
84 u16 local_port; /* Local listening port */
85 u16 remote_port; /* Neighbor destination port */
86 int multihop; /* Number of hops if multihop */
87 int strict_bind; /* Bind listening socket to local address */
88 int ttl_security; /* Enable TTL security [RFC 5082] */
89 int compare_path_lengths; /* Use path lengths when selecting best route */
90 int med_metric; /* Compare MULTI_EXIT_DISC even between routes from differen ASes */
91 int igp_metric; /* Use IGP metrics when selecting best route */
92 int prefer_older; /* Prefer older routes according to RFC 5004 */
93 int deterministic_med; /* Use more complicated algo to have strict RFC 4271 MED comparison */
94 u32 default_local_pref; /* Default value for LOCAL_PREF attribute */
95 u32 default_med; /* Default value for MULTI_EXIT_DISC attribute */
96 int capabilities; /* Enable capability handshake [RFC 5492] */
97 int enable_refresh; /* Enable local support for route refresh [RFC 2918] */
98 int enable_as4; /* Enable local support for 4B AS numbers [RFC 6793] */
99 int enable_extended_messages; /* Enable local support for extended messages [draft] */
100 u32 rr_cluster_id; /* Route reflector cluster ID, if different from local ID */
101 int rr_client; /* Whether neighbor is RR client of me */
102 int rs_client; /* Whether neighbor is RS client of me */
103 u32 confederation; /* Confederation ID, or zero if confeds not active */
104 int confederation_member; /* Whether neighbor AS is member of our confederation */
105 int passive; /* Do not initiate outgoing connection */
106 int interpret_communities; /* Hardwired handling of well-known communities */
107 int allow_local_as; /* Allow that number of local ASNs in incoming AS_PATHs */
108 int allow_local_pref; /* Allow LOCAL_PREF in EBGP sessions */
109 int gr_mode; /* Graceful restart mode (BGP_GR_*) */
110 int llgr_mode; /* Long-lived graceful restart mode (BGP_LLGR_*) */
111 int setkey; /* Set MD5 password to system SA/SP database */
112 /* Times below are in seconds */
113 unsigned gr_time; /* Graceful restart timeout */
114 unsigned llgr_time; /* Long-lived graceful restart stale time */
115 unsigned connect_delay_time; /* Minimum delay between connect attempts */
116 unsigned connect_retry_time; /* Timeout for connect attempts */
117 unsigned hold_time, initial_hold_time;
118 unsigned keepalive_time;
119 unsigned error_amnesia_time; /* Errors are forgotten after */
120 unsigned error_delay_time_min; /* Time to wait after an error is detected */
121 unsigned error_delay_time_max;
122 unsigned disable_after_error; /* Disable the protocol when error is detected */
123 u32 disable_after_cease; /* Disable it when cease is received, bitfield */
124
125 char *password; /* Password used for MD5 authentication */
126 int check_link; /* Use iface link state for liveness detection */
127 int bfd; /* Use BFD for liveness detection */
128 };
129
130 struct bgp_channel_config {
131 struct channel_config c;
132
133 u32 afi;
134 const struct bgp_af_desc *desc;
135
136 ip_addr next_hop_addr; /* Local address for NEXT_HOP attribute */
137 u8 next_hop_self; /* Always set next hop to local IP address (NH_*) */
138 u8 next_hop_keep; /* Do not modify next hop attribute (NH_*) */
139 u8 missing_lladdr; /* What we will do when we don' know link-local addr, see MLL_* */
140 u8 gw_mode; /* How we compute route gateway from next_hop attr, see GW_* */
141 u8 secondary; /* Accept also non-best routes (i.e. RA_ACCEPTED) */
142 u8 gr_able; /* Allow full graceful restart for the channel */
143 u8 llgr_able; /* Allow full long-lived GR for the channel */
144 uint llgr_time; /* Long-lived graceful restart stale time */
145 u8 ext_next_hop; /* Allow both IPv4 and IPv6 next hops */
146 u8 add_path; /* Use ADD-PATH extension [RFC 7911] */
147 u8 import_table; /* Use c.in_table as Adj-RIB-In */
148
149 uint rest[0]; /* Remaining items are reconfigured separately */
150 struct rtable_config *igp_table_ip4; /* Table for recursive IPv4 next hop lookups */
151 struct rtable_config *igp_table_ip6; /* Table for recursive IPv6 next hop lookups */
152 };
153
154 #define NH_NO 0
155 #define NH_ALL 1
156 #define NH_IBGP 2
157 #define NH_EBGP 3
158
159 #define MLL_SELF 1
160 #define MLL_DROP 2
161 #define MLL_IGNORE 3
162
163 #define GW_DIRECT 1
164 #define GW_RECURSIVE 2
165
166 #define BGP_ADD_PATH_RX 1
167 #define BGP_ADD_PATH_TX 2
168 #define BGP_ADD_PATH_FULL 3
169
170 #define BGP_GR_ABLE 1
171 #define BGP_GR_AWARE 2
172
173 /* For GR capability common flags */
174 #define BGP_GRF_RESTART 0x80
175
176 /* For GR capability per-AF flags */
177 #define BGP_GRF_FORWARDING 0x80
178
179 #define BGP_LLGR_ABLE 1
180 #define BGP_LLGR_AWARE 2
181
182 #define BGP_LLGRF_FORWARDING 0x80
183
184 #define BGP_GRS_NONE 0 /* No GR */
185 #define BGP_GRS_ACTIVE 1 /* Graceful restart per RFC 4724 */
186 #define BGP_GRS_LLGR 2 /* Long-lived GR phase (stale timer active) */
187
188 #define BGP_BFD_GRACEFUL 2 /* BFD down triggers graceful restart */
189
190
191 struct bgp_af_caps {
192 u32 afi;
193 u8 ready; /* Multiprotocol capability, RFC 4760 */
194 u8 gr_able; /* Graceful restart support, RFC 4724 */
195 u8 gr_af_flags; /* Graceful restart per-AF flags */
196 u8 llgr_able; /* Long-lived GR, RFC draft */
197 u32 llgr_time; /* Long-lived GR stale time */
198 u8 llgr_flags; /* Long-lived GR per-AF flags */
199 u8 ext_next_hop; /* Extended IPv6 next hop, RFC 5549 */
200 u8 add_path; /* Multiple paths support, RFC 7911 */
201 };
202
203 struct bgp_caps {
204 u32 as4_number; /* Announced ASN */
205
206 u8 as4_support; /* Four-octet AS capability, RFC 6793 */
207 u8 ext_messages; /* Extended message length, RFC draft */
208 u8 route_refresh; /* Route refresh capability, RFC 2918 */
209 u8 enhanced_refresh; /* Enhanced route refresh, RFC 7313 */
210
211 u8 gr_aware; /* Graceful restart capability, RFC 4724 */
212 u8 gr_flags; /* Graceful restart flags */
213 u16 gr_time; /* Graceful restart time in seconds */
214
215 u8 llgr_aware; /* Long-lived GR capability, RFC draft */
216
217 u16 af_count; /* Number of af_data items */
218
219 struct bgp_af_caps af_data[0]; /* Per-AF capability data */
220 };
221
222 #define WALK_AF_CAPS(caps,ac) \
223 for (ac = caps->af_data; ac < &caps->af_data[caps->af_count]; ac++)
224
225
226 struct bgp_socket {
227 node n; /* Node in global bgp_sockets */
228 sock *sk; /* Real listening socket */
229 u32 uc; /* Use count */
230 };
231
232 struct bgp_conn {
233 struct bgp_proto *bgp;
234 struct birdsock *sk;
235 u8 state; /* State of connection state machine */
236 u8 as4_session; /* Session uses 4B AS numbers in AS_PATH (both sides support it) */
237 u8 ext_messages; /* Session uses extended message length */
238
239 struct bgp_caps *local_caps;
240 struct bgp_caps *remote_caps;
241 timer *connect_timer;
242 timer *hold_timer;
243 timer *keepalive_timer;
244 event *tx_ev;
245 u32 packets_to_send; /* Bitmap of packet types to be sent */
246 u32 channels_to_send; /* Bitmap of channels with packets to be sent */
247 u8 last_channel; /* Channel used last time for TX */
248 u8 last_channel_count; /* Number of times the last channel was used in succession */
249 int notify_code, notify_subcode, notify_size;
250 byte *notify_data;
251
252 uint hold_time, keepalive_time; /* Times calculated from my and neighbor's requirements */
253 };
254
255 struct bgp_proto {
256 struct proto p;
257 struct bgp_config *cf; /* Shortcut to BGP configuration */
258 u32 local_as, remote_as;
259 u32 public_as; /* Externally visible ASN (local_as or confederation id) */
260 u32 local_id; /* BGP identifier of this router */
261 u32 remote_id; /* BGP identifier of the neighbor */
262 u32 rr_cluster_id; /* Route reflector cluster ID */
263 int start_state; /* Substates that partitions BS_START */
264 u8 is_internal; /* Internal BGP session (local_as == remote_as) */
265 u8 is_interior; /* Internal or intra-confederation BGP session */
266 u8 as4_session; /* Session uses 4B AS numbers in AS_PATH (both sides support it) */
267 u8 rr_client; /* Whether neighbor is RR client of me */
268 u8 rs_client; /* Whether neighbor is RS client of me */
269 u8 route_refresh; /* Route refresh allowed to send [RFC 2918] */
270 u8 enhanced_refresh; /* Enhanced refresh is negotiated [RFC 7313] */
271 u8 gr_ready; /* Neighbor could do graceful restart */
272 u8 llgr_ready; /* Neighbor could do Long-lived GR, implies gr_ready */
273 u8 gr_active_num; /* Neighbor is doing GR, number of active channels */
274 u8 channel_count; /* Number of active channels */
275 u8 summary_add_path_rx; /* Summary state of ADD_PATH RX w.r.t active channels */
276 u32 *afi_map; /* Map channel index -> AFI */
277 struct bgp_channel **channel_map; /* Map channel index -> channel */
278 struct bgp_conn *conn; /* Connection we have established */
279 struct bgp_conn outgoing_conn; /* Outgoing connection we're working with */
280 struct bgp_conn incoming_conn; /* Incoming connection we have neither accepted nor rejected yet */
281 struct object_lock *lock; /* Lock for neighbor connection */
282 struct neighbor *neigh; /* Neighbor entry corresponding to remote ip, NULL if multihop */
283 struct bgp_socket *sock; /* Shared listening socket */
284 struct bfd_request *bfd_req; /* BFD request, if BFD is used */
285 ip_addr source_addr; /* Local address used as an advertised next hop */
286 ip_addr link_addr; /* Link-local version of source_addr */
287 event *event; /* Event for respawning and shutting process */
288 timer *startup_timer; /* Timer used to delay protocol startup due to previous errors (startup_delay) */
289 timer *gr_timer; /* Timer waiting for reestablishment after graceful restart */
290 uint startup_delay; /* Delay (in seconds) of protocol startup due to previous errors */
291 btime last_proto_error; /* Time of last error that leads to protocol stop */
292 u8 last_error_class; /* Error class of last error */
293 u32 last_error_code; /* Error code of last error. BGP protocol errors
294 are encoded as (bgp_err_code << 16 | bgp_err_subcode) */
295 };
296
297 struct bgp_channel {
298 struct channel c;
299
300 /* Rest are BGP specific data */
301 struct bgp_channel_config *cf;
302 pool *pool; /* XXXX */
303
304 u32 afi;
305 u32 index;
306 const struct bgp_af_desc *desc;
307
308 HASH(struct bgp_bucket) bucket_hash; /* Hash table of route buckets */
309 struct bgp_bucket *withdraw_bucket; /* Withdrawn routes */
310 list bucket_queue; /* Queue of buckets to send (struct bgp_bucket) */
311
312 HASH(struct bgp_prefix) prefix_hash; /* Prefixes to be sent */
313 slab *prefix_slab; /* Slab holding prefix nodes */
314
315 rtable *igp_table_ip4; /* Table for recursive IPv4 next hop lookups */
316 rtable *igp_table_ip6; /* Table for recursive IPv6 next hop lookups */
317 ip_addr next_hop_addr; /* Local address for NEXT_HOP attribute */
318 ip_addr link_addr; /* Link-local version of next_hop_addr */
319
320 u32 packets_to_send; /* Bitmap of packet types to be sent */
321
322 u8 ext_next_hop; /* Session allows both IPv4 and IPv6 next hops */
323
324 u8 gr_ready; /* Neighbor could do GR on this AF */
325 u8 gr_active; /* Neighbor is doing GR (BGP_GRS_*) */
326
327 timer *stale_timer; /* Long-lived stale timer for LLGR */
328 u32 stale_time; /* Stored LLGR stale time from last session */
329
330 u8 add_path_rx; /* Session expects receive of ADD-PATH extended NLRI */
331 u8 add_path_tx; /* Session expects transmit of ADD-PATH extended NLRI */
332
333 u8 feed_state; /* Feed state (TX) for EoR, RR packets, see BFS_* */
334 u8 load_state; /* Load state (RX) for EoR, RR packets, see BFS_* */
335 };
336
337 struct bgp_prefix {
338 node buck_node; /* Node in per-bucket list */
339 struct bgp_prefix *next; /* Node in prefix hash table */
340 u32 hash;
341 u32 path_id;
342 net_addr net[0];
343 };
344
345 struct bgp_bucket {
346 node send_node; /* Node in send queue */
347 struct bgp_bucket *next; /* Node in bucket hash table */
348 list prefixes; /* Prefixes in this bucket (struct bgp_prefix) */
349 u32 hash; /* Hash over extended attributes */
350 ea_list eattrs[0]; /* Per-bucket extended attributes */
351 };
352
353 struct bgp_export_state {
354 struct bgp_proto *proto;
355 struct bgp_channel *channel;
356 struct linpool *pool;
357
358 struct bgp_proto *src;
359 rte *route;
360 int mpls;
361
362 u32 attrs_seen[1];
363 uint err_withdraw;
364 };
365
366 struct bgp_write_state {
367 struct bgp_proto *proto;
368 struct bgp_channel *channel;
369 struct linpool *pool;
370
371 int mp_reach;
372 int as4_session;
373 int add_path;
374 int mpls;
375
376 eattr *mp_next_hop;
377 adata *mpls_labels;
378 };
379
380 struct bgp_parse_state {
381 struct bgp_proto *proto;
382 struct bgp_channel *channel;
383 struct linpool *pool;
384
385 int as4_session;
386 int add_path;
387 int mpls;
388
389 u32 attrs_seen[256/32];
390
391 u32 mp_reach_af;
392 u32 mp_unreach_af;
393
394 uint attr_len;
395 uint ip_reach_len;
396 uint ip_unreach_len;
397 uint ip_next_hop_len;
398 uint mp_reach_len;
399 uint mp_unreach_len;
400 uint mp_next_hop_len;
401
402 byte *attrs;
403 byte *ip_reach_nlri;
404 byte *ip_unreach_nlri;
405 byte *ip_next_hop_data;
406 byte *mp_reach_nlri;
407 byte *mp_unreach_nlri;
408 byte *mp_next_hop_data;
409
410 uint err_withdraw;
411 uint err_subcode;
412 jmp_buf err_jmpbuf;
413
414 struct hostentry *hostentry;
415 adata *mpls_labels;
416
417 /* Cached state for bgp_rte_update() */
418 u32 last_id;
419 struct rte_src *last_src;
420 rta *cached_rta;
421 };
422
423 #define BGP_PORT 179
424 #define BGP_VERSION 4
425 #define BGP_HEADER_LENGTH 19
426 #define BGP_MAX_MESSAGE_LENGTH 4096
427 #define BGP_MAX_EXT_MSG_LENGTH 65535
428 #define BGP_RX_BUFFER_SIZE 4096
429 #define BGP_TX_BUFFER_SIZE 4096
430 #define BGP_RX_BUFFER_EXT_SIZE 65535
431 #define BGP_TX_BUFFER_EXT_SIZE 65535
432
433 static inline int bgp_channel_is_ipv4(struct bgp_channel *c)
434 { return BGP_AFI(c->afi) == BGP_AFI_IPV4; }
435
436 static inline int bgp_channel_is_ipv6(struct bgp_channel *c)
437 { return BGP_AFI(c->afi) == BGP_AFI_IPV6; }
438
439 static inline int bgp_cc_is_ipv4(struct bgp_channel_config *c)
440 { return BGP_AFI(c->afi) == BGP_AFI_IPV4; }
441
442 static inline int bgp_cc_is_ipv6(struct bgp_channel_config *c)
443 { return BGP_AFI(c->afi) == BGP_AFI_IPV6; }
444
445 static inline uint bgp_max_packet_length(struct bgp_conn *conn)
446 { return conn->ext_messages ? BGP_MAX_EXT_MSG_LENGTH : BGP_MAX_MESSAGE_LENGTH; }
447
448 static inline void
449 bgp_parse_error(struct bgp_parse_state *s, uint subcode)
450 {
451 s->err_subcode = subcode;
452 longjmp(s->err_jmpbuf, 1);
453 }
454
455 extern struct linpool *bgp_linpool;
456 extern struct linpool *bgp_linpool2;
457
458
459 void bgp_start_timer(timer *t, uint value);
460 void bgp_check_config(struct bgp_config *c);
461 void bgp_error(struct bgp_conn *c, unsigned code, unsigned subcode, byte *data, int len);
462 void bgp_close_conn(struct bgp_conn *c);
463 void bgp_update_startup_delay(struct bgp_proto *p);
464 void bgp_conn_enter_openconfirm_state(struct bgp_conn *conn);
465 void bgp_conn_enter_established_state(struct bgp_conn *conn);
466 void bgp_conn_enter_close_state(struct bgp_conn *conn);
467 void bgp_conn_enter_idle_state(struct bgp_conn *conn);
468 void bgp_handle_graceful_restart(struct bgp_proto *p);
469 void bgp_graceful_restart_done(struct bgp_channel *c);
470 void bgp_refresh_begin(struct bgp_channel *c);
471 void bgp_refresh_end(struct bgp_channel *c);
472 void bgp_store_error(struct bgp_proto *p, struct bgp_conn *c, u8 class, u32 code);
473 void bgp_stop(struct bgp_proto *p, uint subcode, byte *data, uint len);
474
475 struct rte_source *bgp_find_source(struct bgp_proto *p, u32 path_id);
476 struct rte_source *bgp_get_source(struct bgp_proto *p, u32 path_id);
477
478
479
480 #ifdef LOCAL_DEBUG
481 #define BGP_FORCE_DEBUG 1
482 #else
483 #define BGP_FORCE_DEBUG 0
484 #endif
485 #define BGP_TRACE(flags, msg, args...) do { if ((p->p.debug & flags) || BGP_FORCE_DEBUG) \
486 log(L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
487
488 #define BGP_TRACE_RL(rl, flags, msg, args...) do { if ((p->p.debug & flags) || BGP_FORCE_DEBUG) \
489 log_rl(rl, L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
490
491
492 /* attrs.c */
493
494 static inline eattr *
495 bgp_find_attr(ea_list *attrs, uint code)
496 {
497 return ea_find(attrs, EA_CODE(PROTOCOL_BGP, code));
498 }
499
500 eattr *
501 bgp_set_attr(ea_list **attrs, struct linpool *pool, uint code, uint flags, uintptr_t val);
502
503 static inline void
504 bgp_set_attr_u32(ea_list **to, struct linpool *pool, uint code, uint flags, u32 val)
505 { bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
506
507 static inline void
508 bgp_set_attr_ptr(ea_list **to, struct linpool *pool, uint code, uint flags, struct adata *val)
509 { bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
510
511 static inline void
512 bgp_set_attr_data(ea_list **to, struct linpool *pool, uint code, uint flags, void *data, uint len)
513 {
514 struct adata *a = lp_alloc_adata(pool, len);
515 memcpy(a->data, data, len);
516 bgp_set_attr(to, pool, code, flags, (uintptr_t) a);
517 }
518
519 static inline void
520 bgp_unset_attr(ea_list **to, struct linpool *pool, uint code)
521 { eattr *e = bgp_set_attr(to, pool, code, 0, 0); e->type = EAF_TYPE_UNDEF; }
522
523
524 int bgp_encode_attrs(struct bgp_write_state *s, ea_list *attrs, byte *buf, byte *end);
525 ea_list * bgp_decode_attrs(struct bgp_parse_state *s, byte *data, uint len);
526
527 void bgp_init_bucket_table(struct bgp_channel *c);
528 void bgp_free_bucket_table(struct bgp_channel *c);
529 void bgp_free_bucket(struct bgp_channel *c, struct bgp_bucket *b);
530 void bgp_defer_bucket(struct bgp_channel *c, struct bgp_bucket *b);
531 void bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b);
532
533 void bgp_init_prefix_table(struct bgp_channel *c);
534 void bgp_free_prefix_table(struct bgp_channel *c);
535 void bgp_free_prefix(struct bgp_channel *c, struct bgp_prefix *bp);
536
537 int bgp_rte_better(struct rte *, struct rte *);
538 int bgp_rte_mergable(rte *pri, rte *sec);
539 int bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best);
540 struct rte *bgp_rte_modify_stale(struct rte *r, struct linpool *pool);
541 void bgp_rt_notify(struct proto *P, struct channel *C, net *n, rte *new, rte *old);
542 int bgp_preexport(struct proto *, struct rte **, struct linpool *);
543 int bgp_get_attr(struct eattr *e, byte *buf, int buflen);
544 void bgp_get_route_info(struct rte *, byte *buf);
545
546
547 /* packets.c */
548
549 void bgp_dump_state_change(struct bgp_conn *conn, uint old, uint new);
550 const struct bgp_af_desc *bgp_get_af_desc(u32 afi);
551 const struct bgp_af_caps *bgp_find_af_caps(struct bgp_caps *caps, u32 afi);
552 void bgp_schedule_packet(struct bgp_conn *conn, struct bgp_channel *c, int type);
553 void bgp_kick_tx(void *vconn);
554 void bgp_tx(struct birdsock *sk);
555 int bgp_rx(struct birdsock *sk, uint size);
556 const char * bgp_error_dsc(unsigned code, unsigned subcode);
557 void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsigned subcode, byte *data, unsigned len);
558
559 void bgp_update_next_hop(struct bgp_export_state *s, eattr *a, ea_list **to);
560
561
562 /* Packet types */
563
564 #define PKT_OPEN 0x01
565 #define PKT_UPDATE 0x02
566 #define PKT_NOTIFICATION 0x03
567 #define PKT_KEEPALIVE 0x04
568 #define PKT_ROUTE_REFRESH 0x05 /* [RFC2918] */
569 #define PKT_BEGIN_REFRESH 0x1e /* Dummy type for BoRR packet [RFC7313] */
570 #define PKT_SCHEDULE_CLOSE 0x1f /* Used internally to schedule socket close */
571
572 /* Attributes */
573
574 #define BAF_OPTIONAL 0x80
575 #define BAF_TRANSITIVE 0x40
576 #define BAF_PARTIAL 0x20
577 #define BAF_EXT_LEN 0x10
578
579 #define BA_ORIGIN 0x01 /* RFC 4271 */ /* WM */
580 #define BA_AS_PATH 0x02 /* WM */
581 #define BA_NEXT_HOP 0x03 /* WM */
582 #define BA_MULTI_EXIT_DISC 0x04 /* ON */
583 #define BA_LOCAL_PREF 0x05 /* WD */
584 #define BA_ATOMIC_AGGR 0x06 /* WD */
585 #define BA_AGGREGATOR 0x07 /* OT */
586 #define BA_COMMUNITY 0x08 /* RFC 1997 */ /* OT */
587 #define BA_ORIGINATOR_ID 0x09 /* RFC 4456 */ /* ON */
588 #define BA_CLUSTER_LIST 0x0a /* RFC 4456 */ /* ON */
589 #define BA_MP_REACH_NLRI 0x0e /* RFC 4760 */
590 #define BA_MP_UNREACH_NLRI 0x0f /* RFC 4760 */
591 #define BA_EXT_COMMUNITY 0x10 /* RFC 4360 */
592 #define BA_AS4_PATH 0x11 /* RFC 6793 */
593 #define BA_AS4_AGGREGATOR 0x12 /* RFC 6793 */
594 #define BA_LARGE_COMMUNITY 0x20 /* RFC 8092 */
595
596 /* Bird's private internal BGP attributes */
597 #define BA_MPLS_LABEL_STACK 0xfe /* MPLS label stack transfer attribute */
598
599 /* BGP connection states */
600
601 #define BS_IDLE 0
602 #define BS_CONNECT 1 /* Attempting to connect */
603 #define BS_ACTIVE 2 /* Waiting for connection retry & listening */
604 #define BS_OPENSENT 3
605 #define BS_OPENCONFIRM 4
606 #define BS_ESTABLISHED 5
607 #define BS_CLOSE 6 /* Used during transition to BS_IDLE */
608
609 #define BS_MAX 7
610
611 /* BGP start states
612 *
613 * Used in PS_START for fine-grained specification of starting state.
614 *
615 * When BGP protocol is started by core, it goes to BSS_PREPARE. When BGP
616 * protocol done what is neccessary to start itself (like acquiring the lock),
617 * it goes to BSS_CONNECT.
618 */
619
620 #define BSS_PREPARE 0 /* Used before ordinary BGP started, i. e. waiting for lock */
621 #define BSS_DELAY 1 /* Startup delay due to previous errors */
622 #define BSS_CONNECT 2 /* Ordinary BGP connecting */
623
624
625 /* BGP feed states (TX)
626 *
627 * RFC 4724 specifies that an initial feed should end with End-of-RIB mark.
628 *
629 * RFC 7313 specifies that a route refresh should be demarcated by BoRR and EoRR packets.
630 *
631 * These states (stored in c->feed_state) are used to keep track of these
632 * requirements. When such feed is started, BFS_LOADING / BFS_REFRESHING is
633 * set. When it ended, BFS_LOADED / BFS_REFRESHED is set to schedule End-of-RIB
634 * or EoRR packet. When the packet is sent, the state returned to BFS_NONE.
635 *
636 * Note that when a non-demarcated feed (e.g. plain RFC 4271 initial load
637 * without End-of-RIB or plain RFC 2918 route refresh without BoRR/EoRR
638 * demarcation) is active, BFS_NONE is set.
639 *
640 * BFS_NONE, BFS_LOADING and BFS_REFRESHING are also used as load states (RX)
641 * with correspondent semantics (-, expecting End-of-RIB, expecting EoRR).
642 */
643
644 #define BFS_NONE 0 /* No feed or original non-demarcated feed */
645 #define BFS_LOADING 1 /* Initial feed active, End-of-RIB planned */
646 #define BFS_LOADED 2 /* Loading done, End-of-RIB marker scheduled */
647 #define BFS_REFRESHING 3 /* Route refresh (introduced by BoRR) active */
648 #define BFS_REFRESHED 4 /* Refresh done, EoRR packet scheduled */
649
650
651 /* Error classes */
652
653 #define BE_NONE 0
654 #define BE_MISC 1 /* Miscellaneous error */
655 #define BE_SOCKET 2 /* Socket error */
656 #define BE_BGP_RX 3 /* BGP protocol error notification received */
657 #define BE_BGP_TX 4 /* BGP protocol error notification sent */
658 #define BE_AUTO_DOWN 5 /* Automatic shutdown */
659 #define BE_MAN_DOWN 6 /* Manual shutdown */
660
661 /* Misc error codes */
662
663 #define BEM_NEIGHBOR_LOST 1
664 #define BEM_INVALID_NEXT_HOP 2
665 #define BEM_INVALID_MD5 3 /* MD5 authentication kernel request failed (possibly not supported) */
666 #define BEM_NO_SOCKET 4
667 #define BEM_LINK_DOWN 5
668 #define BEM_BFD_DOWN 6
669 #define BEM_GRACEFUL_RESTART 7
670
671 /* Automatic shutdown error codes */
672
673 #define BEA_ROUTE_LIMIT_EXCEEDED 1
674
675 /* Well-known communities */
676
677 #define BGP_COMM_NO_EXPORT 0xffffff01 /* Don't export outside local AS / confed. */
678 #define BGP_COMM_NO_ADVERTISE 0xffffff02 /* Don't export at all */
679 #define BGP_COMM_NO_EXPORT_SUBCONFED 0xffffff03 /* NO_EXPORT even in local confederation */
680
681 #define BGP_COMM_LLGR_STALE 0xffff0006 /* Route is stale according to LLGR */
682 #define BGP_COMM_NO_LLGR 0xffff0007 /* Do not treat the route according to LLGR */
683
684 /* Origins */
685
686 #define ORIGIN_IGP 0
687 #define ORIGIN_EGP 1
688 #define ORIGIN_INCOMPLETE 2
689
690
691 #endif